[Pgpool-hackers] pgpool-II ideas

[Yoshiyuki Asaba]

Hi,

From: Jeff Davis <jdavis.pgpool at yahoo.com>
Subject: Re: [Pgpool-hackers] pgpool-II ideas
Date: Tue, 19 Jun 2007 09:33:56 -0700 (PDT)

> I think that there's still a problem if the INSERT/UPDATE/DELETE only
> lock the destination table, and not the source table.

You are right. It is unsafe.


> If my thinking is correct, we need:
> (1) All COMMITs to be ordered exactly the same on all nodes
> (2) each statement to be started in the same relative position between
> COMMITs of other transactions
> 
> for any transactions that could affect each other.

I think your solution needs to serialize all writing query. There is a
performance issue.

So I'm planning to implement the following specification:

  pgpool checks CommandComplete tags of INSERT/UPDATE/DELETE. They are
  included the number of updated rows. If they differ, a transaction
  is aborted by pgpool.

pgpool switches this specification or not by a new parameter.

What do you think?
--
Yoshiyuki Asaba
y-asaba at sraoss.co.jp